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Kinetic Behavior of Microencapsulated β‐Galactosidase
Author(s) -
Wadiak D. T.,
Carbonell R. G.
Publication year - 1975
Publication title -
biotechnology and bioengineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.136
H-Index - 189
eISSN - 1097-0290
pISSN - 0006-3592
DOI - 10.1002/bit.260170806
Subject(s) - lactose , chemistry , membrane , kinetics , mass transfer , chromatography , limiting , analytical chemistry (journal) , biochemistry , physics , quantum mechanics , mechanical engineering , engineering
Escherichia coli β ‐ D ‐galactosidase (E.C. 3.2.1.23) was immobilized in cellulose nitrate membrane microcapsules and the reaction kinetics with o ‐nitrophenyl‐β‐ D ‐galactopyranoside (ONPG), lactose, and whole milk were studied using both continuous stirred tank and packed bedreactor configurations. The results of the experiments gave effectiveness factors of 0.3 for ONPG, 0.6 to 0.7 for lactose in solution, andclose to unity for lactose in milk. Using a coupled mass transfer and kinetic model, it was possible to estimate the permeability of the microcapsule membrane from the reactor data. Membrane permeabilities on the order of 5 × 10 −3 and 3 × 10 −4 cm/sec were estimated for ONPG and lactose, respectively. It was determined that the membrane was the limiting mass transfer resistance for the overallreaction. The analysis showed that within the microcapsule, the reaction is reaction rate limited for lactose and slightly diffusion limitedfor ONPG.